feat: fusdc advancer with fees

[0xpatrickdev]

refs: #10390

Description

• Add FeeConfig to privateArgs so deployers can adjust fees over time (terms are immutable)
• Adds FeeTools for calculating net advance and fee splits
• Integrates FeeTools with Advancer

Security Considerations

• None really for these specific changes. We might need to think about timing from when the Advancer calls calculateAdvance and the Settler calls calculateSplit, as the FeeConfig values might change.

• From a product POV, users might pay more in fees than the net advance they receive. So we might consider a config parameter for a "minimum request amount".

Scaling Considerations

None really, mainly contains AmountMath computation.

Documentation Considerations

Includes jsdoc and code comments

Testing Considerations

Includes unit tests for FeeTools, attempting to cover all foreseeable scenarios. A bit light on testing integrations with the advancer and settler.

Upgrade Considerations

N/A, unreleased

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Base branch is changed to master. Please re-run the integration tests by adding 'force:integration' label.